Large composite structures and a process for fabricating large composite structures

ABSTRACT

In a process for fabricating large structures, a composite material panel is continuously pultruded in a pultrusion die assembly and cut transversely to the process direction to provide panel sections. The panel sections can be sufficiently long to extend from one end to an opposite end of the structure. The panel sections are assembled with a joint along adjacent edges using steel-to-composite and composite-to-composite joining technology. The joints can be integrated into the panel longitudinal edges, or separate joint assemblies can be fabricated. In this manner, fewer joints are required. A variety of in-plane and out-of-plane joint assemblies are provided.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] Benefit under 35 U.S.C. § 119(e) is claimed of U.S. ProvisionalApplication No. 60/434,131, filed Dec. 17, 2002, the disclosure of whichis incorporated by reference herein.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] The invention was made with Government support under SBIR GrantContract #N00014-02-M-0086. The Government has certain rights in theinvention.

BACKGROUND OF THE INVENTION

[0003] In certain applications, large scale structures such as buildingsand ships are fabricated from steel, a traditional structural material.Similarly, a deckhouse on a ship may be fabricated in a shipyard fromsteel panels. In such structures, a single wall, floor, or ceiling ofthe building may be formed from a number of steel panels weldedtogether. The entire structure is further welded to the steel deck ofthe ship.

[0004] Compared to steel, composite materials are much lighter in weightand exhibit good corrosion resistance. Composite materials are formed ofreinforcing fibers within a resin matrix. Parts fabricated fromcomposite materials can be made strong and stiff and can be used toadvantage in structural applications. However, parts fabricated fromcomposite materials are often more costly than steel parts. The highercost is generally due to the greater cost of the raw materials coupledwith greater tooling and labor costs. Also, composite elements are morecomplex to join than steel plate and frame structures, which aretypically joined relatively simply by welding. Thus, the compositematerials may not be used to replace steel, even if their benefits wouldbe advantageous in a particular application, due to cost considerations.

[0005] The vacuum assisted resin transfer method (VARTM) is a batchprocess that can be used to form composite materials into complexthree-dimensional shapes. This method requires the fabrication of a moldin the final form of the part to the manufactured. The raw material iscut into appropriately sized pieces and laid up in layers in the mold.The distribution media, hoses, vacuum lines and resin lines are set.Then the resin is injected and allowed to cure. The part is thenunbagged and demolded. The support materials must then be disposed ofand the mold cleaned, and the entire process repeated for the next part.This process is costly due to the higher raw material costs, the handlabor required, single part processing, long cure cycle, and the amountof scrap material generated. Thus, the cost per pound of VARTMcomposites is high compared to steel fabrication.

[0006] Pultrusion is another known fabrication process for formingcomposite material parts. Pultrusion is generally more suitable forforming two-dimensional shapes. The initial tooling costs can be high,but pultrusion is a continuous process from which many parts can beformed relatively economically with less labor than VARTM. Thus, incertain applications, pultrusion can be more advantageous than VARTM.

[0007] Both VARTM and pultrusion are not yet as cost efficient as steelfabrication, however. Thus, a composite material fabrication processthat is competitive with steel fabrication for large scale structureswould be beneficial.

SUMMARY OF THE INVENTION

[0008] The present invention relates to a process for fabricating largestructures and to the structures formed by this process. The structuresare formed from a plurality of large pultruded structural panels.Composite-to-composite and steel-to-composite joint designs for theedges of the panels are provided for assembling the panels into astructure.

[0009] More particularly, a continuous composite material panel ispultruded in a pultrusion die assembly. The continuous panel has opposedlongitudinal edges extending in the process direction. After exiting thepultrusion die assembly, the continuous panel is cut transversely to theprocess direction into panel sections of the desired length for theparticular structure. The panel sections are assembled into the desiredstructure by joining two or more panel sections with a joint alongadjacent edges. The joint may be formed by edge details integrated intothe panel's longitudinal edges during the pultrusion process and/or by aseparate joint assembly that interconnects the adjacent panels alongtheir edges. At least some of the panels may be assembled to extend fromone end to an opposite end of the structure. Thus, with the presentinvention, the number of joints required in the structure as a whole canbe minimized.

[0010] Thus, the invention provides a cost- and performance-effectivealternative to welded steel construction. The steel-to-composite andcomposite-to-composite joint designs for both in-plane (bulkhead, deck)and out-of-place (deck to bulkhead, bulkhead to bulkhead) panel jointshave self-fixturing attributes and high unit load capacities. Morestructural applications can take advantage of the reduced weight,corrosion resistance and tailored performance benefits of compositematerials using the present invention.

DESCRIPTION OF THE DRAWINGS

[0011] The invention will be more fully understood from the followingdetailed description taken in conjunction with the accompanying drawingsin which:

[0012]FIG. 1 is an isometric schematic view of a building structureaccording to the present invention;

[0013]FIG. 2 is a schematic illustration of a pultrusion process for usein the present invention;

[0014]FIG. 3A is a schematic illustration of steps in a process ofassembling a structure according to the present invention;

[0015]FIG. 3B is a schematic illustration of further steps in theprocess of FIG. 3A;

[0016]FIG. 3C is a schematic illustration of further steps in theprocess of FIGS. 3A and 3B;

[0017]FIG. 4A is a schematic illustration of steps in an alternativeprocess of assembling a structure according to the present invention;

[0018]FIG. 4B is a schematic illustration of further steps in theprocess of FIG. 4A;

[0019]FIG. 5A is a schematic isometric view of a joint detail for thestructure of FIGS. 3A-4B;

[0020]FIG. 5B is a further schematic isometric view of a joint detailfor the structure of FIGS. 3A-4B;

[0021]FIG. 6A is a schematic illustration of steps in a still furtherprocess of assembling a structure according to the present invention;

[0022]FIG. 6B is a schematic illustration of further steps in theprocess of FIG. 6A;

[0023]FIG. 6C is a schematic illustration of further steps in theprocess of FIGS. 6A and 6B;

[0024]FIG. 6D is a schematic illustration of further steps in theprocess of FIGS. 6A-6C;

[0025]FIG. 7 is a schematic cross sectional view of a panel to panel todeck joint assembly according to the present invention;

[0026]FIG. 8 is a further embodiment of the joint assembly of FIG. 7;

[0027]FIG. 9 is a still further embodiment of the joint assembly of FIG.7;

[0028]FIG. 10 is a still further embodiment of the joint assembly ofFIG. 7;

[0029]FIG. 11 is a schematic cross sectional view of a four-corner jointassembly according to the present invention;

[0030]FIG. 12 is a further embodiment of the joint assembly of FIG. 11;

[0031]FIG. 13 is a still further embodiment of the joint assembly ofFIG. 11;

[0032]FIG. 14 is a schematic view of a two-corner joint assemblyaccording to the present invention;

[0033]FIG. 15 is a schematic cross sectional view of a two-corner jointassembly according to the present invention;

[0034]FIG. 16 is a further embodiment of the joint assembly of FIG. 15;

[0035]FIG. 17 is a further embodiment of a two-corner joint assembly ofthe present invention;

[0036]FIG. 18 is a further embodiment of a four-corner joint assembly ofthe present invention;

[0037]FIGS. 19-25 are further embodiments of joint assemblies accordingto the present invention;

[0038]FIG. 26 is a schematic view of an interlocking joint assemblyintegrated into panel edges;

[0039]FIG. 27 is a schematic view of a joint assembly for a compositepanel to a steel deck;

[0040]FIG. 28 is a schematic illustration of a further assembly processaccording to the present invention;

[0041]FIG. 29 is a schematic illustration of a further step of theassembly process of FIG. 28; and

[0042]FIG. 30 is a schematic illustration of a still further step of theassembly process of FIGS. 28 and 29.

DETAILED DESCRIPTION OF THE INVENTION

[0043]FIG. 1 illustrates a multi-level structure, such as a deckhousefor a ship, that can be taken as an example of the present invention.Such a structure 10 may include perimeter walls 12, a bottom floor ordeck 14, a roof deck 16, and intermediate decks or flooring 18. Thestructure may be framed with vertical framing elements 20 spacedperiodically along its length and horizontal or transverse cross beams22 at the level of each deck. The structure's outer or perimeter wallsmay be vertical or tapered somewhat from vertical, as illustrated,depending on the application.

[0044] Such a structure may require a variety of in-plane andout-of-plane joint assemblies to attach all of the various panelsections together to arrive at the desired final structureconfiguration. For example, the perimeter walls of adjacent levels areattached together with in-plane joints. The perimeter walls are attachedto the horizontal deck and ceiling panel sections with out-of-planejoints. Interior walls or bulkheads may require a variety of cornerjoint assembly configurations, depending on the structure's design. Sucha structure may also need to be attached to a preexisting foundationalsurface, such as a steel deck 24.

[0045] The composite material panels and joint assemblies are formedusing a pultrusion process, illustrated schematically in FIG. 2. Thepultrusion process generally is known and will not be described indetail herein. Composite materials are typically formed from glass orcarbon fibers and polyester, vinyl ester, epoxy, or polyurethane resins,although other materials can be used. The composite material panels canbe of any suitable type. They can be sandwich panels with a suitablecore material, such as balsa, foam, honeycomb, stitched cores, orfabric-reinforced cores. The panels can be solid laminates without acore, rib-stiffened or blade-stiffed panels, or cellular core panels.

[0046] According to the present invention, the pultrusion equipment ispreferably located at the site where the structure is to be constructed.On-site fabrication eliminates the need to ship the panels by truck,rail, or barge, which would minimize the size of the panels. Forexample, panels transported by truck can generally be no longer than 53feet, and panels transported by rail can generally be no longer than 80feet. Barged panels can be somewhat longer, but the panel length isstill constrained by the barge's capacity. When the pultrusion equipmentis located at the construction site, the length of a pultruded panel isessentially unlimited. Portions of a pultruded panels can be cut off toform a panel section of any desired length. Preferably, the panelsections are at least four feet in width and the length in the processdirection is at least twice as long as the width. The panels can readilybe formed with greater widths, such as eight feet, ten feet, or more.The length of the panel exiting the pultrusion die assembly isessentially unlimited. The panel is cut across the length to form thepanel sections of any desired length, such as twenty feet, forty feet,one hundred feet, or more. Panel sections can be several hundred feetlong.

[0047] The panel sections are assembled into a structure with a jointalong adjacent longitudinal edges of the panel sections. The panel canbe continuously pultruded with each longitudinal edge in the processdirection having joint details integrated therein. Alternatively, aseparate joint assembly can be fabricated and used to join two panelsections along adjacent longitudinal edges. The separate joint assemblymay be fabricated as a continuous pultrusion that is, like the panel,cut to any desired length. A number of joint details are described withmore particularity below. Preferably, at least a portion of the panelsections are assembled to extend from one end to an opposite end of thestructure. See, for example, panel sections 12 in FIG. 1. In thismanner, the number of joints in the structure can be minimized.

[0048] One embodiment of an assembly process for a structure isillustrated in FIGS. 3A-3C. The structure shown has four levels,although any desired number of levels could be provided. Similarly, thestructure shown has tapered walls, although the walls could be verticalif desired. Also, in the process shown, the structure is assembled on afoundation surface, such as a steel deck. The structure can be, forexample, several hundred feet long.

[0049] In the first step, a steel frame 30 outlining the perimeter ofthe enclosure is welded to the steel deck 32. The steel frame includes ajoint assembly between the horizontal steel deck and the verticalcomposite perimeter panels, described further below. In step 2, wall,floor, and ceiling frame members 34, either composite or steel, areattached to the deck plate frame. Next, a first level of long pultrudedcomposite perimeter panel sections 36 are attached in any suitablemanner, such as with mechanical fasteners or adhesive bonding or both,to the vertical frame members. Then, long pultruded joint assemblies 38are attached to the upper edges of the long perimeter panel sections.Alternatively, the longitudinal lengths of the panel sections can bepultruded with the joint details integrated therein, eliminating theneed for a separate joint assembly. The joint between two wall panelsections and a deck panel section is illustrated with more particularityin FIGS. 5A and 5B. In this example, the joint assembly is cut out toaccommodate the vertical framing elements.

[0050] In step 5, a long pultruded deck panel section 40 is slid ontothe deck beams 34. A plurality of long deck panel sections can be used,placed with the long edges adjacent, if the width of the floor isgreater than the width of a pultruded deck panel section. Next, a secondlevel of long pultruded composite perimeter panel sections 42 areattached to the joint assembly along the upper edge of the first levelof perimeter panel sections, as by adhesive bonding, mechanicalfastening, or both. Then, long joint assemblies 44 are attached to theupper edges of the long perimeter panel sections of the second level. Instep 8, a long pultruded deck panel section (or panel sections) 46 isslid into place.

[0051] In step 9, a third level of continuous long pultruded compositeperimeter panel sections 48 are attached to the joint assembles 44 alongthe upper edges of the second level of perimeter panel sections 42.Next, long joint assemblies 50 are attached to the upper edges of thethird level of perimeter panel sections. The next deck panel section (orpanel sections) 52 is slid into place. The final perimeter panelsections 54 are attached to the upper edges of the third level perimeterpanel sections, and a final panel edge connector 56 is installed on thejoint assembly along the top edge of the perimeter panel sections. Theupper level deck panel section is then slid into place. End walls 60 areadded at each end.

[0052] In another variation of the assembly process, illustrated inFIGS. 4A-4B, a base frame is welded to the steel deck and vertical framemembers are installed as above. However, only the lowest level oftransverse deck beams are installed in step 2. After installation of thefirst level of perimeter panel sections, a deck panel section can bedropped in vertically along the continuous length without interferencefrom the pre-installed transverse deck beams for the upper level decks.The transverse deck beams are then installed following the installationof the deck panel sections for the level immediately below. This processavoids the need to slide the deck panel sections into place.

[0053] In a further alternative assembly process, the structure isassembled upside down, illustrated in FIGS. 6A-6D. In this process, theupper perimeter corner joint pieces are laid out. The top deck panelsection is laid down. As above, several deck panel sections can be laiddown with a longitudinal panel to panel joint therebetween if necessary.Then, transverse beams or joists are laid out. The vertical frameelements are assembled with appropriate fixturing. Top interior deckspace bulkheads are assembled in their desired positions. In step 6, topdeck panel sections are laid onto bulkhead edges and frame tabs. It willbe appreciated that the interior bulkheads can be formed from pultrudedpanel sections and using the joint technology of the present invention.

[0054] Top deck space perimeter panel sections or bulkheads are attachedto the upper perimeter joint pieces. Interdeck joints are attached tothe edges of the perimeter panel sections in step 7. Top deck supportingcross members or joists and then third deck space bulkheads are added.Next, a third deck is added. In step 11, third deck perimeter panelsections or bulkheads and interdeck joints are added. Third decksupporting frame cross members are added. Second deck space interiorbulkheads are placed in their desired locations, and a second deck isadded. In step 15, second deck perimeter panels or bulkheads are added.Then, second deck supporting frame cross members are placed. In step 17,first deck space interior bulkheads are added. Next, the first deckperimeter panels and bulkheads are placed and the main deck joint pieceadded. Then, the entire assembled structure is turned over in place andfixed to the supporting deck.

[0055] A variety of joint assemblies suitable for use in structures suchas described above are illustrated in FIGS. 7-27. The joint assembliesare illustrated as pieces separate from the panel sections. However, itwill be appreciated that the joint details of these joint assemblies canbe readily integrated into the longitudinal, or process direction, edgesof the continuous panel during the pultrusion process. For ease ofdescription, the joint details are described in conjunction withseparate joint assemblies.

[0056] In the assembly of the structure, the elements of the jointassembly and the panel sections are fastened in any suitable manner,such as with a suitable bonding agent, such as epoxy, mechanicalfasteners, or a combination of joining methods. Mechanical fasteners cansuitably be used to provide integrity while the bonding agent is curing.Mechanical fastening can include fasteners such as bolts or screws, orcan include devices that snap together or other interlocking elementsintegrally formed on corresponding portions of the joint to preventremoval once fitted together. By integrating interlocking elements intothe joints, the joints can be self-fixturing.

[0057] A panel-to-panel-to-deck joint assembly 80 is illustrated in FIG.7. This joint assembly joins two linearly aligned panel or plate-likestructures 82, 84 with a third panel or plate-like structure 86, such asa deck, at an angle. In the embodiment illustrated, the joint assemblyis formed in two pieces, a joint member 88 and an angle member 90. Thejoint member includes a lineal piece 92 and a ledge or flange 94. Thelineal piece includes two recesses 96, 98 to receive the two panels 82,84 that are linearly aligned. The angle member 90 sandwiches the edge ofthe third panel 86, such as a deck element, against the joint ledge orflange 94. The joint member and angle member are preferably pultruded toany length desired. In assembly, the deck panel is laid against theflange and the angle member placed against the deck panel. The colinearpanels are inserted into the recesses. All the elements are suitablyfastened. The joint assembly could be formed as one unitary piece withthe angle piece integral with the joint member if desired. In this case,the deck panel is slid or otherwise inserted into the recess between theflange and the angle piece.

[0058] The three panel structures can be formed of a composite materialor a metal such as steel. The joint assembly is particularly suitablefor joining composite material panels to a steel deck or compositepanel. In the embodiment illustrated, the panels 82, 84 are a sandwichtype having a core 102 and face skins 104. The long edges 106 aretapered, and the face skins wrap around and cover the long edges. Thetapered edge improves load transfer across the joint and can be readilyformed in a composite material fabrication process. The deck element 86is illustrated with a rectangular edge, although its edge could betapered as well.

[0059]FIG. 8 illustrates a joint assembly 110 in which the lineal piece112 is disposed at other than a right angle with respect to the flange114, which is suitable for use with perimeter walls angled fromvertical, as shown above in FIG. 1. FIG. 9 illustrates a joint assembly120 in which the colinear panels have been recessed along their longedges 122 so that the lineal piece 124 of the joint assembly lies flushwith the outer surface of the panels. FIG. 10 illustrates a jointassembly 130 in which the deck panel 132 has been recessed to receivethe angle member 134.

[0060] A joint assembly 140 for joining four panels at right angles isillustrated in FIG. 11. This joint assembly is suitable, for example, asan internal bulkhead corner joint. This joint assembly includes fourflanges 144 extending from a central hub 146. Each flange has a recessfor receiving a panel structure 148. The joint assembly can be suitablyformed by pultrusion using suitable insert dies 150, 151 (shown inphantom) to form the recesses and each corner. A number of rods 152 canbe placed in the central hub for strengthening in the joint assembly.FIG. 12 illustrates a joint assembly 160 in which the recesses 162 inthe flanges 164 are tapered to receive panels 166 having tapered cores168 that fit into the recesses and face sheets 170 that extend over theflanges of the joint assembly. FIG. 13 illustrates a joint assembly 180in which the panel edges 182 can be recessed and the flanges 184 can beconfigured to lap the recessed edge. As will be apparent, a combinationof flange designs can be used. Additionally, less than four flanges maybe provided if desired. For example, FIG. 14 illustrates a jointassembly 190 having two flanges for joining two panels at a corner.

[0061] A further joint assembly 200 for joining two panels at a corneris illustrated in FIG. 15. This joint assembly includes two flanges 202integrally joined to form a corner 204 of any desired angle, such as aright angle as shown, and a beam member 206 configured to fit againstthe panel members 208 within the corner. Although a right angle joint isillustrated, it will be appreciated that any desired angle can beprovided. In this embodiment, the flanges are tapered, and the paneledges are recessed to fit over the tapered flanges. The recessed edgesmay be formed during the pultrusion process, or recesses may be machinedinto the edges subsequently. The panels and the joint assembly arefastened in any suitable manner, such as described above. In analternative embodiment of a joint assembly 210 illustrated in FIG. 16,the flanges 212 can be formed separately and fastened together, such aswith a mortise and tenon joint 214.

[0062] A further corner joint assembly 220 is illustrated in FIG. 17.This joint assembly includes an outer corner member 222 and an innercorner member 224. The outer corner member is fastened to the outercorner formed by two panels 226, 228 butted together. The inner cornermember is fastened to the inner corner formed by the two panels. Theinner corner member may include additional reinforcing material forstrengthening if desired.

[0063]FIG. 18 illustrates a joint assembly 230 in which four innercorner members 232 are arranged to fasten three panels together to formfour corners. Two panels 234, 236 are butted against a third panel 238along an interior portion thereof.

[0064] Still further embodiments of joint assemblies are illustrated inFIGS. 19-25. FIG. 23 illustrates a joint assembly that is formed fromthe parts illustrated in FIGS. 19 and 20. FIG. 24 illustrates a jointassembly that is formed from the parts illustrated in FIGS. 20 and 21.FIG. 25 illustrates a joint assembly that is formed from the partsillustrated in FIGS. 20 and 22. Thus, in these cases, a common rightangle part is used to close each joint. It will be appreciated thatother joint configurations are possible, and the particular jointconfiguration will be selected based on the configuration and strengthrequirements of the structure.

[0065]FIG. 26 illustrates an embodiment of a joint assembly 240 in whichthe joint details are integrally formed into the longitudinal edges 242,244 of the panels 246, 248 during pultrusion. One edge 244 includes amale portion and the opposite edge 242 includes a female portion. A tab250 and mating recess 252 are also included to provide interlocking ofthe two portions.

[0066] A joint assembly 260 that is particularly suitable for joining acomposite panel 262 to a steel deck 264 is illustrated in FIG. 27. Thisjoint assembly includes two recesses 266, 268 extending in a directionof elongation. The recesses are preferably tapered. A steel coamingstructure 270 is welded, brazed, riveted, or attached in any othersuitable manner to the steel deck 264. If the steel deck is curved, thelower edge of the steel coaming structure can be curved to mate with thesteel deck. The upper edge 272 of the coaming structure is straight andtapered to form a wedge 274 that fits within the correspondingly taperedlower recess 266 of the joint assembly. A lower edge 276 of a compositepanel fits within the upper recess. In this way, a composite panelhaving a straight lower edge can be fitted to a curved or irregularsteel deck. The coaming structure extends a sufficient distance abovethe deck so that it may be readily inspected and so that debris ormoisture cannot collect. In an alternative, the lower edge of thecomposite panel can be formed with a lower recess to receive the upperedge of the coaming structure.

[0067] Another method for accommodating the complex curvatures of afoundational surface such as a ship's deck is illustrated in FIGS.28-30. A panel is continuously pultruded with a constant cross section.The pultruded panel is cut into sections 290 having the desired lengthsfor the structure. Each panel is trimmed to mate the edge to theexisting curvature, as illustrated in FIG. 29. The joints between thestructure and the foundational surface can be formed using a vacuumassisted resin transfer method. In this case, panels are fixed intoposition (see FIG. 30), fabric materials to form the joint arepositioned in the joint area, the joint area is bagged, and resin isinfused along the joint length. This results in a joint that is able toaccommodate any local irregularities.

[0068] The joint assemblies of the present invention can also befabricated to provide good electromagnetic interference (EMI) shielding.The panels and the joint assembly can be pultruded with their outermostply or plies including conductive fibrous or metallic layers and/orconductivity-enhancing particulate fillers. Referring, for example, toFIG. 7, by tapering the recesses in the lineal piece, the jointassembly's outermost plies can extend beyond the joint edge, therebycovering the seam between the joint assembly and the panels. Suitableconductivity-enhancing layered materials include, for example, fabricsand felts made with electrically conductive metal fiber, solid orperforated thin metal foils, and fabric and felts made with metal-coatedglass or carbon fiber. Layers of conductive fiber or felt can alsoprovide some mechanical strength and stiffness.

[0069] Conductivity-enhancing particulate fillers include, for example,carbon black and various forms of particulate graphite, metal coatedparticles or metal flakes, or carbon nanotubes and nanofibers. Thefillers contribute to overall EMI shielding effectiveness by virtue ofthe inherent electrical conductivity, and by providing additionalconductive paths between the reinforcing fabrics, felts or perforatedsheets. Carbon nanotubes and nanofibers can provide electricalconductivity enhancement at relatively low particulate loadings. Carbonblack is an excellent UV inhibitor and produces a gray color, reducingthe need for painting.

[0070] Locating the EMI shielding layer as the outermost ply reduces therisk associated with delamination of the laminate due to lightningstrikes. Metallic fabric or felt surfaces also provide a continuousmembrane for EMI shielding and good surface area at joints for groundingcomposite structures to steel hull structures. Also, repeated cyclicloading can lead to the development of microcracks, which creatediscontinuities in the EMI shield, leading to leaks. Metallic fabrics orfelts can provide additional grounding paths across areas ofmicrocracking.

[0071] It will be appreciated that the present invention is applicableto a variety of large-scale structures in addition to buildings andships, such as rail cars, building facades, tunnel liners, bridges, orpiers. At least a portion of a ship's hull can be formed according tothe invention. The invention is not to be limited by what has beenparticularly shown and described, except as indicated by the appendedclaims.

What is claimed is:
 1. A process for fabricating a structure,comprising: pultruding a continuous panel in a process direction in apultrusion die assembly, the continuous panel having opposedlongitudinal edges extending in the process direction, each longitudinaledge having an edge profile extending continuously in the processdirection; after the panel exits the pultrusion die assembly, cuttingthe continuous panel across the process direction into panel sections ofdesired lengths; and assembling the panel sections into a structure withat least two panel sections joined with a joint along adjacentlongitudinal edges, the two panel sections having a length of at leasttwenty feet in the process direction.
 2. The process of claim 1, whereinthe edge profiles of the opposed longitudinal edges are pultruded withcomplementary interlocking configurations to form the joint when the twopanel sections are joined along adjacent longitudinal edges.
 3. Theprocess of claim 1, wherein the edge profiles of the opposedlongitudinal edges are recessed to overlap when placed in abutment. 4.The process of claim 1, wherein the longitudinal edges are attached byadhesive bonding, mechanically fastening, or by a combination ofadhesive bonding and mechanically fastening.
 5. The process of claim 1,further comprising pultruding a continuous joint assembly in a processdirection, the joint assembly configured to form the joint joining thetwo panel sections along adjacent longitudinal edges.
 6. The process ofclaim 5, wherein the edge profile of at least one longitudinal edge ispultruded with a flat face.
 7. The process of claim 5, wherein the edgeprofiles of the opposed longitudinal edges are machined to mate with thejoint assembly.
 8. The process of claim 5, wherein the edge profile ofat least one longitudinal edge is tapered to mate with the jointassembly.
 9. The process of claim 5, wherein the continuous panel ispultruded with at least one tapered edge profile to mate with the jointassembly.
 10. The process of claim 1, wherein the joint between the twopanel sections comprises a composite material joint.
 11. The process ofclaim 1, further comprising molding a composite material joint assemblyin place to form the joint between the two panel sections.
 12. Theprocess of claim 1, further comprising molding a joint assembly, thejoint assembly configured to form the joint between the two panelsections.
 13. The process of claim 1, further comprising providing agasket in the joint between the two panel sections.
 14. The process ofclaim 1, further comprising providing caulk in the joint between the twopanel sections.
 15. The process of claim 1, wherein the joint betweenthe two panel sections is flush with surfaces of the two panel sections.16. The process of claim 1, wherein the joint between the two panelsections is flush with outer surfaces of the two panel sections.
 17. Theprocess of claim 1, wherein the two panel sections are assembled to liein a single plane.
 18. The process of claim 1, wherein the two panelsections are assembled with the process direction extendinghorizontally.
 19. The process of claim 1, wherein the two panel sectionsare assembled with the process direction extending vertically.
 20. Theprocess of claim 1, wherein the two panel sections are assembled to liein different planes.
 21. The process of claim 1, wherein the jointbetween the two panel sections comprises a corner joint.
 22. The processof claim 1, further comprising assembling a third panel section, thethird panel section joined to the two panel sections at the jointbetween the two panel sections and lying in a different plane, theprocess direction of the third panel section parallel to the processdirection of the two panel sections.
 23. The process of claim 1, whereinthe continuous panel has a width transverse to the process directiongreater than four feet.
 24. The process of claim 1, wherein thecontinuous panel has a width transverse to the process direction greaterthan eight feet.
 25. The process of claim 1, wherein the two panelsections are at least forty feet long.
 26. The process of claim 1,wherein the two panel sections at least one hundred feet long.
 27. Theprocess of claim 1, wherein the two panel sections are at least twice aslong as wide.
 28. The process of claim 1, further comprising fasteningthe structure to a foundational surface.
 29. The process of claim 28,wherein the foundational surface comprises a metal surface, and furthercomprising: attaching an elongated metal strip to the metal surface, themetal strip having a straight upper edge and a lower edge conforming tothe metal surface; attaching a joint member to the metal strip, thejoint member having an upper portion configured to mate with one of thelongitudinal edges of a panel section; and attaching the panel sectionto the joint member.
 30. The process of claim 29, wherein the metalstrip is attached to the metal surface by welding, brazing, or riveting31. The process of claim 29, wherein the joint member is attached to themetal strip by adhesive bonding, mechanically fastening, or by acombination of adhesive bonding and mechanically fastening.
 32. Theprocess of claim 29, wherein the joint assembly is attached to the panelsection by adhesive bonding, mechanically fastening, or by a combinationof adhesive bonding and mechanically fastening.
 33. The process of claim1, further comprising assembling the structure up-side down andinverting the structure.
 34. The process of claim 1, further comprisingpultruding the continuous panel and assembling the structure at a samelocation.
 35. A structure formed by the process of claim
 1. 36. Thestructure of claim 35, wherein the structure comprises an enclosurehaving walls and a roof element.
 37. The structure of claim 36, whereinthe enclosure further includes framing members, the panel sectionsattached to the framing members.
 38. The structure of claim 36, whereinthe enclosure further includes internal walls and external walls. 39.The structure of claim 36, wherein the panel sections form a facade overfurther wall elements.
 40. The structure of claim 36, wherein the panelsections form vertical walls of the enclosure.
 41. The structure ofclaim 36, wherein the panel sections form tapered walls of theenclosure.
 42. The structure of claim 35, wherein the enclosurecomprises a multi-story building.
 43. The structure of claim 35, whereinthe enclosure comprises a shipboard structure.
 44. The structure ofclaim 35, wherein the structure further comprises at least a portion ofa ship's hull.
 45. The structure of claim 35, wherein the structurefurther includes a deck element.
 46. The structure of claim 35, whereinthe structure including the deck element comprises a bridge or a pier.47. The structure of claim 1, wherein the continuous panel is formedfrom glass fibers or carbon fibers and a resin matrix comprisingpolyester resin, vinyl ester resin, epoxy resin, or polyurethane resin.48. A structure formed at least in part of panels, comprising: aplurality of panel sections formed of a composite material extendingcontinuously in a longitudinal direction, each panel section having alength in the longitudinal direction and a width transverse to thelongitudinal direction, the length at least twice as long as the width,and having opposed longitudinal edges extending along the longitudinaldirection; at least two panel sections having a length of at leasttwenty feet; and a joint formed between the longitudinal edges ofadjacent ones of the panel sections.
 49. The structure of claim 48,wherein the joint comprises an interlocking element formed on onelongitudinal edge and a mating interlocking element formed on anopposite longitudinal edge of at least a portion of the panel sections,whereby adjacent panel sections fit together.
 50. The structure of claim49, wherein the longitudinal edges are further attached with adhesivebonding, additional mechanical fastening, or a combination of adhesivebonding and additional mechanical fastening.
 51. The structure of claim48, wherein the joint comprises a joint assembly extendinglongitudinally between opposed longitudinal edges of adjacent panelsections, the joint assembly attached to the adjacent panel sections byadhesive bonding, mechanical fastening, or a combination of adhesivebonding and mechanical fastening.
 52. The structure of claim 48, whereinthe joint comprises a joint assembly comprising a lineal piece and aflange extending in the longitudinal direction, the lineal pieceincluding a first longitudinally extending recess receiving one panelsection longitudinal edge and a second longitudinally extending recessreceiving a second panel section longitudinal edge, the first and secondpanel sections aligned in a plane, a third panel section attached to theflange of the joint assembly in a further plane at an angle to the planeof the first and second panel sections.
 53. The structure of claim 52,wherein the joint assembly further comprises an angle piece holding thethird panel section against the flange.
 54. The structure of claim 53,wherein the third panel section includes a recess to receive the anglepiece.
 55. The structure of claim 52, wherein the joint assembly linealpiece lies flush against the first and second panel sections.
 56. Thestructure of claim 48, wherein the joint comprises a joint assemblycomprising a longitudinally extending hub and a plurality oflongitudinally extending flanges extending from the hub, each flangeattached to a longitudinal edge of a respective panel section.
 57. Thestructure of claim 56, wherein the flanges of the joint assembly includea recess therein to receive the longitudinal edge.
 58. The structure ofclaim 56, wherein the longitudinal edges of the panel sections includerecesses and the flanges of the joint assembly are received in therecesses.
 59. The structure of claim 56, wherein the flanges and thelongitudinal edges of the respective panel sections include cut outrecesses that overlap.
 60. The structure of claim 56, wherein the jointassembly comprises two flanges.
 61. The structure of claim 56, whereinthe joint assembly comprises four flanges.
 62. The structure of claim48, wherein the joint comprises a joint assembly comprising alongitudinally extending corner element and a longitudinally extendingbeam member, the corner element attached to longitudinal edges of twopanel sections to form a corner, the beam member attached within thecorner to the two panel sections.
 63. The structure of claim 48, whereinthe joint comprises a joint assembly comprising a longitudinallyextending outer corner member and a longitudinally extending innercorner member, two panel sections abutting along respective longitudinaledges to form a corner, the outer corner member and the inner cornermember attached to the abutting panel sections at the corner.
 64. Thestructure of claim 48, wherein the joint comprises a joint assemblycomprising a plurality of longitudinally extending inner corner members,two panel sections abutting a third panel section at an interior portionto form four corners, the inner corner members fastened at each of thefour corners.
 65. The structure of claim 48, wherein the joint comprisesa joint assembly comprised at least in part of a composite material. 66.The structure of claim 48, wherein the joint comprises a joint assemblyformed at least in part of metal.
 67. The structure of claim 48, whereinthe length of at least a portion of the panel sections is greater than40 feet.
 68. The structure of claim 48, wherein the length of at least aportion of the panel sections is greater than 100 feet.
 69. Thestructure of claim 48, wherein the structure comprises an enclosure, thepanel structures forming at least a portion of the perimeter walls ofthe enclosure.
 70. The structure of claim 48, wherein the structurefurther includes one or more panel sections formed of metal.
 71. A jointassembly for attaching a composite panel section to a metal deck,comprising: a metal deck; a coaming attached to and extending outwardlyfrom the metal deck; a longitudinally extending joint member, a lowerlongitudinally extending recess formed in the joint member, the coamingreceived in the lower recess, and an upper longitudinally extendingrecess; a composite panel section, the composite panel section receivedin the upper recess.
 72. The joint assembly of claim 71, wherein themetal deck is curved at least in part, and the coaming is curved tomatch the curvature of the metal deck, the coaming having an upper edgethat is straight.
 73. The joint assembly of claim 71, wherein the lowerrecess is tapered.
 74. The joint assembly of claim 71, wherein the upperrecess is tapered.